i finished the assembly of the prototype last night and it worked from the start.
now we have one PCB containing the actual circuitry of the complete VCO (waveshapers included), size 4in x 2.2in, and an additional adapter board for the for the front panel components (LFO mod/cap/LED included), size 4in x 3.1in eurorack form factor.
so now the actual VCO PCB is now smaller than just the core board from the 1st run, but is still providing MTA-100 connector footprints for easier manual wiring (if needed/wanted). and i now made a complex footprint to adapt a super matched pair (like the lm394) or your hand matched 3904 transistors.

Don't know if i ever mentioned this before, but the Expo converter from the 4046 VCO works really well (and for me in an astonishing precise way) in the ASM1 VCO... have finished two of them and tuning was very easy, both oscillators track really close, so far my best result regarding tracking of a VCO...
Also i now used LF op amps in the Expo converter and thus slightly changed it a bit and added the positive and negative FM method as used on the buchla 258 VCO's.

On my two 4046 VCO it is limited somehow at higher range or at lower range which i had to make some compromises to handle both...

First of i think it has something to do with my CD4046, still managed it to get another brand, and also i finally decided to order a lot of polysterene caps which i can Exchange for the Polypropylene caps build in there, might improve things a bit i hope..._________________https://soundcloud.com/bastian-j

Sorry got it the wrong way around... too much poly's left me poly-confused

After reading a guide, regarding caps and their use in audio circuits, i don't know exactly what web site it was, but it was from one of the more known guys (Marc Bareille perhaps) active in the DIY scene, who compared the different cap types and their use, giving a rough guide for their use.

For a long time i used polysterene (wima MKS) caps in most circuits, which seem not as useful in VCO's or VCF's. So from that list one of the closest replacements for silver mica were polypropylene caps (in my case Wima FKP2 and MKP2) from which i now ordered a few of some values to exchange them.

WIMA MKS is polyester NOT polysterene.
polypropylen is good for s/h applications IIRC.

the best choice for timing caps is polysterene (i.e. styroflex) or ceramic C0G/NP0. polysterene is THE classic VCO cap, however, meanwhile the new C0G appeared and they have a much more civil footprint.

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